Details

Date

1861

Author

Pasteur

Contribution

a. Reported that some organisms can live without oxygen (anaerobic fermentation).

Reference

Carter

Notes

Wrote that production of butyric acid from sugar was caused by an organism capable of living without oxygen. The title refers to "animalcules infusoires". According to Geison, he noted that the rod-like organism was motile (hence "animalcule") but not when near edge of slide. Suspected effect of air and confirmed by bubbling air through liquid fermentation, thereby killing the "rods." The concept was extended to fermentation and putrefaction in general (with aerobes living near the surface of a fermentation and utilizing the byprobucts of fermentation. Cohn later named Pasteur's butyric "ferment" Bacillus subtilis.